Rand saw



March 3, 1942. 1 HEDGPETH 2,274,923

BAND SAW Filed Feb. 27, 1939 6 Sheets-Sheet l i I Invert/b1. ermljgWZ/EMarch 3, 1942. T. 1.. HEDGPETH BAND SAW Filed Feb. 27, 1939 6Sheets-Sheet 5 March 3, 1942. T. L. HEDGPETH BAND S AW Filed Feb. 27,1939 6 Sheets-Sheet 4 IMUGIGM T/zrmoLJ/cgwveik T. L. HEDGPETH I March 3,1942.

BAND SAW Filed Feb. 27, 1959 6 Sheets-Sheet 6 Patented Mar. 3, 19422,274,923 BAND SAW Theron L. Hedgpeth, Oak Par-hill assignor to DoroMetal Products Company, Chicago, Ill., a corporation of IllinoisApplication February 27, 1939, Serial N... 258,669

.8Claims.

Th present invention relates to wood working tools, and is particularlyconcerned with improvements in band saws.

One of the objects of the invention is the pro-v vision of an improvedband saw structure which is adapted to facilitate the adjustment of thetilt of the upper pulley axis from the front of the machine so that thisadjustment can be made while the machine is in operation.

When a piece of work is being backed oi! the blade, there is a tendencyto pull the blade sidewise, and it is very important at this time to beable to efiect an adjustment of the tilt of the upper pulley axis. Suchan adjustment may cause the upper pulley to tilt back, at its top, sothat the pulley crown will cause the blade to ride back tightly againstits guide roller, which lies adjacent the work, and which engages therear side of the blade. The machines of the prior art of which I amaware are not so constructed that this adjustment may be accomplishedwhile a machine is operating, because they require the operator to goback of the machine to adjust the tilt of the upper pulley axis.

Another object of the invention is the provision of an improved band sawstructure, including means for effecting an adjustment of the upperpulley tilt and means for guarding the hand of the operator from themechanism when an adjustment is effected with the machine in operation.

Another object of the invention is the provision of an improved band sawstructure, including a tiltable table and an angularity indicatorlocated on the standard in such a position that the angularity of thetable is in position to be observed by the operator at all times and isaccurately indicated on the standard.

Another object. of the invention is the provision of an improvedadjusting means for the angularity of tilt of the upper pulley axis,which is 'eflective exactly at the center of the upper pulley by meansof the provision of a hollow pulley shaft in which the adjusting meansis located.

Other objects and advantages of the invention will be apparent from thefollowing description and the accompanying drawings, in which similarcharacters of reference indicate similar parts throughout the severalviews.

Referring to the six sheets of drawings accompanying this specification,

Fig. 1 is a front view in perspective of a band saw embodying myinvention;

Fig. 2 is a fragmentary vertical sectional view, taken on the plane ofthe line 22 of Fig. 1,

looking in the direction of the arrows, showing the details of structureof support of the two pulleys of the band saw. and showing theangularity indicator;

Fig. 3 is a fragmentary vertical sectional view, taken through thatportion of the band saw located adjacent the table top, showing thedetails of structure of the pivotally supported table and the angularityindicator, taken on the plane of the line 3-4 of Fig. 5;

Fig. 4 is a fragmentary elevational view of the same structure as Fig.3, taken from the rear side of Fig. 1;

Fig. 5 is a fragmentary vertical sectional view, taken "on the plane ofthe line 5-5 of Fig. 3, looking in the direction of the arrows, showingfurther details of structure of the table and its adjustable supportingdevices;

Fig. 6 is a fragmentary horizontal sectional view, taken through thestandard and angularity indicator, on the plane of the line 6-6 of Fig.2, looking in the direction of the arrows;

Fig. 7 is a fragmentary horizontal sectional view, taken on the planeofthe line 1-! of Fig. 2, showing further details of structure of theangularity indicator;

Fig. 8 is a fragmentary vertical sectional view, taken on the plane ofthe line 88 of Fig. 2, showing further details of the structure of theangularity indicator;

Fig. 9 is a fragmentary vertical sectional view, taken on the same planeas Fig. 2, showing the details of structure of the upper band saw pulleyand its means for effecting an adjustment of the pulley axis;

Fig. 10 is a fragmentary horizontal sectional view, taken on the planeof the line ill-III of Fig. 2, looking in the direction of the arrows,showing the details of structure of the lide and guides for supportingthe upper pulley shaft and permitting an adjustment of the tightness ofthe band saw; and

Fig. 11 is a fragmentary vertical sectional view, taken on the plane ofthe line of Fig. 2, looking in the direction of the arrows.

Referring to Figs. 1 and 2, the band saws 20 constructed according to.the invention are preferably mounted on a base 2|, which may support themotor 22. The base 2| may comprise a pair of castings, each castingbeing formed with a pair of feet 23, and with a top flange 24 forsupporting the band saw.

one of which is utilized for pivotally supporting A. 'ai'inotor stand 2to which the motor 22 is bolted. The weight o the motor 22 may thus beutilized for maintaining a tight condition of the drive belt 21, whichextends about the motor pulley and the drive pulley 28 (Fig. 2) of theband saw.

The band saw 28 preferably comprises a vertical cast metal frame,provided at its bottom with feet 29, serving as attaching flanges, bymeans of which the band saw is secured by bolts to the base 2|.

The band saw frame 30has an upwardly extending frame member 3I at theright side for supporting the table 32. It also has an upwardlyextending frame member or standard 33 at the left side, viewing themachine from the front, as seen in Fig. 1, for supporting the pivotallymounted saw guard 34 and for carrying the over-hanging arm ",whichsupports the upper band saw pulley.

The standard 33 is provided with a pair of pintle brackets 36, which maybe bolted or otherwise secured thereto, and which are provided withupwardly projecting pintles 31 engaged in apertures in the pintle lugs38, which project laterally from the saw guard 34.

The saw guard 34 comprises a connecting frame member 39 and a pair ofguard housings 4|, 4|, each of which has a cylindrical boundary wall 42and a radially inwardly extending wall 43. These two walls enclose thesurface of the pulleys and the band saw at the periphery of the pulleys,and the guard is provided with enlarged apertures 44, exposing the majorportion of the surface of the pulley inward of the periphery of thepulley.

The guard may also have a wall 45 adjoining the cylindrical walls 42 forthe purpose of strengthening the guard, and the wall 45 has a slot 46 ineach case for passing the band saw.

The upper guard housing 43 may be provided with an integral, downwardlyopen socket 41 for receiving a work light.

The edge of the table 32 carries a guide bar 48, upon which a work fence49 is slidably supported, and the. work fence may be substantially asshown in my prior Patent No. 2,075,282 on Bench saw, issued March 20,1937.

In addition to the tiltable table 22 the standard 33 may support awooden table section 58, comprising a plane, rectangular wooden tabletop, which may be secured to the standard as shown in Fig. 3. A pair ofright angle brackets II and 52 may be employed. The bracket 52 has onevertical flange secured by a screw bolt 53 to the standard 33. Thebracket I has its horizontal flange 54 secured by wood screws or othersuitable fastening means to the wooden table section 50. Both brackets5|, 52 have vertical flanges 55, 56, which may be secured together bybolts or other suitable fastening devices, the bolts having suitableclearance in their apertures so as to provide for a small amount ofadjustment in the wooden table section 59.

The band saw frame has its table-support-- ing portion 3| provided witha plurality of rein- 5) with a pair of substantially semicylindricalbearing surfaces 12, 13 located in spaced relation to each other andadapted to engage complementary cylindrical trunnion surfaces 14, 15 ona trunnion member 16 carried by the table top.

The trunnion member I6 comprises a cast metal member having the sidewalls." .joined by flanges I8 and provided with the foot flanges 19, bymeans of which the bolts may secure the trunnion fixture to the lowerside of the table p.

The sidewalls 11 support the substantially cylindricalitrunnion surfaces14, I5, and adjacent each bearing surface the trunnion fixture 16 isprovided" with a laterally projecting retaining flange 89, 8|. Thisretaining flange is adapted to be engaged on its upper side in each caseby a bracket 82, which is carried by the table-supporting bracket 69. Aplurality of the brackets 82 are preferably used on each side of thetable bracket 69, as shown in Fig. 3, and each of the retaining brackets82 has an attachment flange 83 for receiving a bolt, which passesthrough an aperture in the bracket 82 and is threaded into a bore in thebracket 69.

Each retaining bracket 82 also has laterally projecting retaining flange84 of substantially cylindrical shape and curved on the same center asthe surfaces 12 and 14 so that the cylindrical flange 84 may engage onthe upper side of the laterally projecting flanges 88 or ill and holdthe cylindrical surfaces 12, I4 and l3, 15 respectively, in slidingengagement with each other.

Thus the table 32 is mounted for pivotal movement upon an axis which islocated at the center of generation of the cylindrical surfaces 12-15.This center is preferably located in the plane of the top of the table32 at the point 85, where the band saw passes through a slot 85 in thetable 32.

The table 32 may be provided with an enlarged cylindrical aperture 86,and a pressure plate 81, having a suitable slot 85, may be pressed intoa counterbore 88 above the bore 86.

The table is preferably provided with a crank shaft bearing bracket 90,which has an attachment flange 92 secured by bolts to the under side ofthe table 32 and has a diagonally and downwardly extending arm 93, whichis formed with a pair of spaced bearing flanges 94.

The spaced bearing flanges are provided with threaded apertures forreceiving a pair of conically pointed set screws 95, which are locked inplace by lock nuts 96 and which engage in complementary aperturesoppositely disposed on the sides of a bearing member 91. v

The bearing member 91 has an axially extending bore for rotatablyreceiving the crank shaft 98, and thrust bearings 99 are secured on theshaft 98 at each end of the bearing 91 by means of pins or othersuitable securing devices, which secure the thrust bearings fixedly tothe shaft 98. At one end the shaft 98 carries a conven tional crank armI89 provided with a handle Illl and counter-weight I02. At the other endthe shaft 98 is provided with relatively coarse screw threads I93, whichengage in a complementarily threaded bore in a cylindrical screwfollower I01, which is pivotally mounted by means of set screws I04 in abracket I05 fixedly carried by the frame of the band saw.

A pair of lock nuts I86 on the extreme threaded end of the shaft 98 actas a stop member for limiting the outward movement of the shaft 98. Thetable 32 is thus adapted to be tilted by retating crank III with thehandle Ill, and is also adapted to be held in any predetermined positionto which it is moved because of the non-reversible characteristics ofthe screw I03 and the follower I01.

The table 32 comprises a cast metal member, having an upper planesurface III, which is provided with one or more slots III for receivinga complementary bar which carries a mitre gauge. The table 32 aso has andepending border flange H2 and a plurality of transverse reinforcingribs H3.

In order to indicate the angularlity of the table at all times, thetable 32 is provided with a bracket II4 secured to its lower sideadjacent the left edge of the table (Fig. 3), and the bracket H4 ispivotally connected to a connecting link H6 by means of a screw boltpassing through an aperture in the bracket and link, and provided with anut.

The link Ill is pivotally connected in a similar way to the right end ofa lever III by means of a bolt H1. The lever H6 is pivotally mountedadjacent its middle by means of the bolt III, which is fixedly securedin a threaded bore in the hub member H9 on the frame 00, and the lever II6 is provided with an elongated slot I at its left end (Fig. 3).

An indicator bar I2I is slidably mounted between the front wall I22 ofthe standard and an elongated guide member I23 (Fig. 2), and theindicator bar I 2| has a ninety degree twist at m so that its lower end15 parallel to the flat sides of the lever H6.

The indicator bar I2I is pivotally and slidably secured to the lever H0by means of a screw bolt and nut, the bolt I25 passing through acylindrical aperture in the indicator bar I2I and through the slot I20in the lever H6.

The indicator bar I2I has its face provided with suitable indicia,comprising transverse scale division marks, which may be in the form ofgrooves and located at regularly spaced intervals, and numericalindicia, comprising a zero and scale division numbers, such as 5, 10,15, etc., for indicating the degrees of tilt. The scale division numberspreferably extend oppositely in two directions, that is, upward anddownward from the zero point, as shown in Fig. 1, and are suitablylocated so that they are visible at a window aperture I26 in the guidemember I23.

The forward wall I22 of the standard 33 is provided with threaded boresI21, I23 to receive the screw bolts I29, I30, (Figs. 6 to 8) whichextend through bores I in the guide member I23 at diagonally oppositecorners of the guide member.

The guide member I23 comprises a cast metal member, which is formed withlaterally projecting attachment flanges I32 and with a central bodyhaving a longitudinally extending groove I33 in the rear side thereof.The groove I33 is overhung by inwardly projecting flanges I34 at eachside at the rear, and is thus provided with a substantially rectangulargroove I33 for receiving the indicator bar I2I, which is slidablymounted in the guide member I23.

The groove I33 communicates with the window aperture I26 (Fig. 7), whichis preferably outwardly beveled at I36 so as to provide a maximumvisibility.

The front surface of the guide member I23 is provided with a groove I36in one side for receiving the pointer I31, which may consist of a sheetmetal member provided with an aperture located immediately in front ofthe indicia on the indicator bar I2I. A single screw bolt I40, threadedinto the guide member I23 and passing through the aperture I23, securesthe pointer I31 and permits a slight pivotal adjustment of the pointerso that the pointer may be caused to indicate accurately the angulartilt of the table, and particularly the zero or level position, to whichthe table and pointer are adjusted.

In order to prevent the binding of the Indicator bar I2I in the guidemember I23 and to permit a certain amount of tolerance in themanufacture of the cast metal parts, guide member I23 is adjustablymounted on the standard 33. This is done by means of two additionalscrew bolts I4l, I42 located in threaded bores I43 in the guide memberI23 at the other two diagonally opposite corners thereof.

As the screw bolts I4I, I42 are relatively short, their ends are notthreaded into the standard, but bear against the face of the standard.The screw bolts I29 and I may thus be backed out until there is asuitable clearance between the the screws I 4|, I42 inward to engage thestandard 33.

The screws I29, I30 bind the guide member I23 to the standard, whilescrews I H, I42 press the guide member I23 outward from the standard.Between the adjustment of these two pairs of screws, the guide memberI23 may be fixedly secured in such position on the standard that theindicator bar I2I will slide freely and will not bind in its groove I33.

The frame member 30 of the band saw is provided with a verticallyextending body flange I45 (Fig. 2), which serves with the reinforcingflanges 6I-64 to support a cylindrical bearing hub 65.

The bearing hub 65 is provided with a through bore I41, but adjacenteach end it is cast with an inwardly extending rib I48, which may becounterbored at I49 to provide an accurately sized bore for receivingthe two anti-friction bearing I50, I5I. The outer races of thesebearings have a tight frictional flt in the counterbores I49. The innerraces of the bearings, which are supported by suitable balls in theouter races, have bores for passing the lower shaft I52. Shaft I52 isprovided with a thrust bearing I53 at the right side of theanti-friction bearing I5I, secured to the shaft by a set screw, and atits right end the shaft I52 fixedly supports the pulley 28, which issuitably keyed and secured to the shaft by a key and a set screw.

The other end of the shaft I52 carries the low 3 er band saw pulley I55,which is also suitably keyed to the shaft I52, to rotate with the shaft.The end of the shaft is provided with a threaded bore I56 for receivingthe fiat headed screw bolt I51, which secures a partially sphericalshield plate I53 to the shaft and pulley I65.

The shield plate has a countersunk, centrally located aperture I59 forengagement with the screw, so that the screw head is flush with theshield plate. The right side of the shield plate (Fig. 2), adjacent itsouter edge, engages the face of the pulley I and insures the securementof the pulley I55 on the shaft I52.

The shieldv I53 also provides a smooth finished surface for the exposedcenter of the lower band screw saw pulley I66, so that there are noprolecting bolts that might become engaged by the clothin of the user.

The lower band saw pulley III may comprise a cast metal member providedwith an approximately cylindrical rim I30, and a radial body flange I6I,joining the rim to a hub I82. The hub I82 has a bore I63 for receivingthe shaft I62. The rim I80 is provided with a cmwned surface I84, whichmay be covered by a continuous sheet rubber band I68 of complementaryshape, adapted to give a better traction between the pulley and band sawI83, and to protect the sharp edges of the band sawfrom engagement withthe metallic parts of the pulley.

The lower pulley I66 is preferably provided with a more pronounced crownthan the upper pulley I61, in order that the lower pulley may keep itsband saw I66 on the pulley in spite of pivotal adjustments of the axisof the upper pulley.

The band saw I66 comprises an endless steel band saw of conventionalform and of suitable length so that it may be tightly mounted upon thepulleys I55, I61.

The standard 33 is provided with a laterally projecting arm 35 whichoverhangs the table 32. The arm 35 is adapted to support the upper bandsaw pulley I61, its bearings, and associated mechanism. For this purposethe laterally projecting arm 35 supports a cast metal guide fixure I10(Fig. 9), which is provided at its lower end with a pair of attachingflanges "I.

The attaching flanges I'll are secured to the arm 35 by suitable screwbolts I12 (Fig. 10). The fixture I10 is provided with a dove-tailshapedgroove I13, the open side of which faces toward the upper band sawpulley I61 and is adapted to receive the dove-tail-shaped slider Theslider I14 is substantially smaller than the dove-tailed groove so thatan adjustment may be provided in the form of a metal strip I15 mountedbetween one side of the guide I14 and the wall of the dove-tailed groove"3. i

The metal strip I15 has a conical socket I16, which receives the conicalend of an adjustment I 11. The adjustment screw I11 is adjustablymounted in a threaded bore I18 and is secured in place by lock nut I18.The adjust ment screw I11 and strip I15 permit the dovetailed slider I14to be driven against the opposite side of the dove-tailed groove I13 tosecure relatively tight sliding fit, so that there is no possibility oflooseness or rattling.

Any wear which may occur can readily be v taken up by means of theadjustment screw I11. The slider I14 has its beveled surfaces I80 formedon the rearwardly extending legs I8I, carried by a fiat body I82, sothat the slider may be hollow at I83.

A rearwardly projecting lug I84 (Fig. 9)is carried by the slider andprovided with a threaded bore I85 for receiving the threaded portion I86of an adjustment rod I81. The adjustment rod I81 extends throughsuitable bores in the fixture I10, and is provided with a hand wheel I88at the bottom for its rotation. The hand wheel I88 may engage an annularshoulder I89, and may be secured in place by a nut I90 on the threadedreduced portion I8I.

At its upper end the fixture I10 is provided with a plate I82, having abore I83 for passing the rod I81, which is of reduced section at thispoint.

The plate I82 is secured to fixture I10 be increased by rotating thehand wheel I88 in a counter clockwise direction in Fig. 8, to

drive the slider I14 upward. The adjustment rod I81 then reacts downwardon the spring I88.

Referring to Figs. 8 and 9, the slider I14 pivotally supportsa'shaft-supporting member 288 for the upper band saw pulley I81. Theshaft-supporting member 288 comprises a cast metal member having a lowercylindrical body 2", which is provided with a bore 282, within which thehollow shaft 283 has a tight frictional fit.

The hub 28I is carried by a pair of side flanges 204, which are joinedat the rear side by a flange 208, but are separated at the top toreceive the forwardly projecting lug 288. The shaft-supporting member288 is pivotally mounted on the lug 208, projecting from the slider I14,by means of a pin or bolt 281, and thus the shaft 203 is mounted forpivotal movement about the center of the bolt 281. y

The shaft 203 is provided with a centrally located through bore "landwith a threaded counterbore 208. A threaded rod 2I8 extends through thebore 208 and has its threaded end 2 threaded into the bore 288, and itsextreme end 2I2 bears on the inner surface 2I3 of slider I14. At itsouter end the rod 2I8 is provided with a knurled thumb wheel 2, and apartially spherical sheet metal shield 2I8 is engaged about the rod 2I0and held against the end of the shaft 203 by a compression spring 2I8.Thus the shield may be mounted out of contact with the upper pulley I61,but in position to protect the hands of the operator during anadjustment from any projecting bolts or other parts carried by thewheel.

The shield is, of course, held against rotation, since it is mounted onthe fixed shaft 283. The rod 2I0 may be provided with a spherical end sothat there is an engagement between the rod 2I0 and surface 2I3 only atthe center or axis of the rod.

The upper pulley I61 comprises a cylindrical hub member 2I1, a radialflange 2I3, and a rim 2I8. The rim is provided with a crowned surface220 and covered with a resilient band of rubber 22I for engaging the sawblade I66. The upper pulley is similar in shape to the lower one exceptfor the amount of crown on the pulley and the structure of the pulley atthe hub 2".

The hub 2" is provided with a centrally located bore 222, and the borecontains near its inner end an inwardly projecting flange 223 adapted toengage the outer race of an anti-friction hearing 224. This race has africtional fit in a bore 225, and the shaft 203 may have a cylindricalenlargement 226 for engaging the inner race of the anti-friction bearing224.

The hearing may be provided with a suitable oil seal 221, and a feltwasher 228 may be interposed between the end of the hub 20I and thebearing 224. At its front end the hub 2" is provided with a similarcounterbore 238 and an inwardly extending fiange 23I, and the shaft 203has a reduced cylindrical portion 232, these three parts engaging theanti-friction bearing 233 in the same manner as described for the rearbearing 224.

A nut 234 and washer 236 secure the inner race of bearing 2 on the shaft263 by means of a threaded portion 236. An annular retaining plate 231is secured by screw bolts 236 to the hub 2" of the pulley I61, and theplate 231 overhangs the outer race of the bearing 23! to retain it inthe bore 230. Bolts 236, plate 231, and nut 234 are all concealed byshield 2I6, but are not engaged by the shield, as they are carried bythe rotating pulley I61.

By means of the rotation of the knurled thumb wheel 2 and rod 2I6, thetilt of the upper pulley I" may be changed at any time, and particularlywhen the machine is in operation, without going to the back of themachine, and without danger to the operator. It is important, whenbacking work off such a band saw blade, that provision be made forcausing the blade to engage its guide rollers tightly, as the lateralthrust on the saw band may otherwise cause the saw band to run off oneor the other pulley.

For this purpose the operator may tilt the upper pulley I61 toward theright, at the top, by securing thumb wheel 2 in a clockwise direction,when it is desired to back oil a work piece from the saw band. Thisadjustment may, of course, be made from the front of the machine, withthe present structure.

This is a marked advantage over the devices of the prior art, in whichit was necessary to go to the back of the machine to effect any suchadjustment.

The band saw I66 is mounted on the pulleys I55, I61 and housed withinthe cover 39, 40, 4I. It is guided above the table 32 by guides whichare carried by a depending frame member 240 (Fig. 3), having a rotatablymounted grooved roller 242 carried by a bolt 243 passing through lug244.

Metal blocks 245, slidably mounted in guides 246 and secured by setscrews 241, are located on the opposite sides of the blade, with asuitable clearance.

A set of guide blocks, similar to blocks 245, above the table, isprovided at 248 below the table, (Fig. 5) and another grooved roller 24!is located below the table. Both these guide members are carried byadjustably mounted shanks 256, 25I, and the roller 249 is tilteddiagonally in a direction opposite to the diagonal tilt of the roller242.

The shape of the roller is such that there is practically a continuouscontact engagement between the walls of the groove of the roller and therear edge of the saw blade I66. Ordinarily the operation of the band sawwill be apparent from the description of its parts.

When it is desired to back work off the saw blade, the operator, whousually stands in front of that part of the machine shown in Fig. 1, mayadjust the tilt of the upper pulley by turning on the knurled thumbwheel 2I4. A right hand turn on this thumb wheel will cause theadjustment rod 2I6 to move the fixed shaft 203 toward the left, as theend 2I2 of the rod is fixed against axial movement.

This causes the upper part of the rim 2I9 of the pulley I61 to tiltbackward, or toward the right, in Fig. 9, and the crown of that pulleytends to keep the band saw in the middle of the pulley while the bandsaw is operating. This causes the band saw to engage tightly against itsrear guides and causes the band saw to resist any tendency of forwardmovement of the band saw, due to the friction of the work on the sidesof the saw as the work is withdrawn.

This may be accomplished when the machine is still or when it isoperating, and the guard structure at the upper pulley protects the handof the operator while he is effecting an adjustment of the pulley tilt.

The adjusting means is effective attire axis of the pulley by means ofthe stationary hollow pulley shaft. The table of my band saw is providedwith an angularity indicator, mounted on the standard, which is visibleto the operator at all times, and indicates at all times the angularityof the table top. This indicator structure is provided with a guidewhich is capable of such adjustment that there is no possibility ofbinding of the indicator in its guide.

While I have illustrated a preferred embodiment of my invention, manymodifications may be made without departing from the spirit of theinvention, and I do not wish to be limited to the precise details ofconstruction set forth, but desire to avail myself of all changes withinthe scope of the appended claims.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States, is:

1. In a band saw tool-supporting structure, comprising a frame member, aslider engaged in va complementary groove in said frame member,

threaded means located in a threaded bore in said slider and extendingin a direction to adjust the tension of a band saw, said threaded meansbeing supported by a compression spring engaging said frame member, ahollow shaft pivotally mounted on said slider, said hollow shaftrotatably supporting a band saw pulley, and a threaded adjustment rodmounted in a threaded bore in said shaft and engaging said slider, saidrod projecting from the forward end of said shaft whereby the angularityof tilt of the pulley may be adjusted from the front of the machine.

2. In a band saw tool-supporting structure, comprising a frame member, aslider engaged in a complementary groove in said frame member, threadedmeans located in a threaded bore in said slider and extending in adirection to adjust the tension of a band saw, said threaded means beingsupported by a compression spring engaging said rame member, a hollowshaft pivotally mounted on said slider, said hollow shaft rotatablysupporting a band saw pulley, and a threaded adjustment rod mounted in athreaded bore in said shaft and engaging said slider, said rodprojecting from the forward end of said shaft whereby the angularity oftilt of the pulley may be adjusted from the front of the machine, saidshaft having anti-friction bearings interposed between said shaft andpulley and said shaft projecting from said pulley, and a shield locatedon said rod and engaging the end of said shaft for guarding the hand ofan operator from rotating parts on said pulley, said rod having a headand compression spring means between said head and said shield forholding said shield in predetermined position, engaging said shaft andhaving a clearance with said pulley.

3. In a band saw the combination of a supporting frame with upper andlower band saw pulleys, a band saw carried by said pulleys, pulleyshafts for said upper and lower pulleys carried by said frame, one ofsaid pulley shafts being hollow, means for supporting said latter pulleylow shaft whereby the pulley carried by said hollow shaft may have thedirection of its axis adjusted during the operation of the machine tomaintain the band saw on said pulleys under predetermined conditions. I

4. In a band saw the combination of a supporting frame with upper andlower band saw pulleys, a band saw carried by said pulleys, pulleyshafts for said upper and lower pulleys carried by said frame, one ofsaid pulley shafts being hollow, means for supporting said latter pulleyshaft pivotally upon said frame at a pivot point spaced from the axis ofsaid latter shaft, and a threaded means mounted in said hollow shaft andhaving threaded engagement therewith and projecting from both ends ofsaid hollow shaft, said threaded means engaging a part carried by saidframe substantially at the axis of said hollow shaft whereby the pulleycarried by said hollow shaft may have the direction of its axis adjustedduring the operation of the machine to maintain the band saw on saidpulleys under predetermined conditions, and ,manualmeans carried by theends of said threaded means opposite to its engagement with the framefor engagement with the hand in adjusting the tilt of the hollow pulleyshaft.

5. In a band saw the combination of a supporting frame with upper andlower band saw pulleys, a band saw carried bysaid pulleys, pulley shaftsfor said upper and lower pulleys carried by said frame, one of saidpulley shafts being hollow, means for supporting said latter pulleyshaft pivotally upon said frame at a pivot point spaced from the axis ofsaid latter shaft, and a threaded means mounted in said hollow shaft andhaving threaded engagement therewith and projecting from both ends ofsaid hollow shaft, said threaded means engaging a part carried by saidframe substantially at the axis of said hollow shaft whereby the pulleycarried by said hollow shaft may have the direction of its axis adjustedduring the operation of the machine to maintain the band saw on saidpulleys under predetermined conditions, said threaded means having ashield mounted thereon engaging the end of said hollow shaft, saidshield having a clearance with the pulley carried by said hollow shaft,and resilient means engaging the shoulder on said threaded meansengaging said shield to hold the shield in predetermined position.

6. An arrangement for adjustably supporting the pulley of a band saw atpredetermined tilt and band saw tension comprising a support, a threadedmember carried by said support and rotatably mounted thereon, manualmeans carried by said threaded member for its rotation, resilient meansengaging said support and engaging a shoulder carried by said threadedmember for supporting the threaded member and placing a predeterminedtension on the band saw, a slider carried by the support having athreaded bore engaging said threaded member, a shaft supportingleverpivotally mounted on said slider and having a bore for supporting ashaft adjacent said slider, a hollow shaft carried by said lever forsupporting a band saw pulley, and a threaded member threadedly mountedinside said hollow shaft and having one end engaging said slider, saidthreaded member projecting from the other end of said hollow shaftwhereby the tilt of the pulley may be adjusted and the position of theslider may be adjusted while the machine is operating.

7. In a mechanism for adjusting the position of a band saw pulley, thecombination of a support with a lever pivotally carried by said supportdepending therefrom, said lever having a transverse bore, a hollow shaftfixedly secured in said bore, said shaft having a threaded bore, athreaded rod in said shaft threadedly engaging said latter bore, saidrod projecting from said shaft at each end, manual means carried by theouter end of said rod opposite to said pivoted lever, and a band sawpulley rotatably mounted on said shaft whereby the angular position ofthe shaft and pulley may be adjusted by said threaded means while thepulley is rotating.

8. In a mechanism for adjusting the position of a band saw pulley, thecombination of a support with a lever pivotally carried by said supportdepending therefrom, said lever having a transverse bore, a hollow shaftfixedly secured in said bore, said shaft having a threaded bore, athreaded rod in said shaft threadedly engaging said latter bore, saidrod projecting from said shaft at each end, manual means carried by theouter end of said rod opposite to said pivoted lever, and a band sawpulley rotatably mounted on said shaft whereby the angular position ofthe shaft and pulley may be adjusted by said threaded means while thepulley is rotating, a metal shield carried by said rod and engaging theouter end of said shaft, and compression spring means between saidshield and said manual means for holding said shield in predeterminedposition on said rod, said shield having a clearance with respect tosaid pulley.

THERON L. HEDGPETH.

